Question

Which of the following is the inverse of the function given below?

Answer 1

Rearrange so x  is the subject:-

(im assuning  the f unction f(x)  = (x + 2) / 7):-


f(x) = (x + 2)/7

7f(x)  = x + 2

x = 7f(x) - 2

replace f(x) by  x and x by another function 

f = 7x - 2


Its D

Answer 2

Answer:

$\Rightarrow f^{-1}(x)=\frac{7x-2}{7}$

Step-by-step explanation:

We  have been given the function

$f(x)=x+\frac{2}{7}$

Let f(x)=y

$y=x+\frac{2}{7}$

Taking LCM we get

$y=\frac{7x+2}{7}$

After rearranging the terms we will find the value of x in terms of y.

$x=\frac{7y-2}{7}$

$f^{-1}(y)=\frac{7y-2}{7}$

$\Rightarrow f^{-1}(x)=\frac{7x-2}{7}$